Dynamo-electric machine



(No Model.) v r 3 Sheets-Sheet 1.

E. A.EDWARDS..

DYNAMO ELECTRIC MACHINE. No. Z8l 985. Patented July 24, 1883.

rs. PETERS FhJIu-Lllhognphur, Washington, a c.

3 Sheets--Sheet (No Model.)

B A EDWARDS DYNAMO ELECTRIC MACHINE.

Patented July"24, 1883. I

.ewa

(No Model.) a Sheets-Shet a;

E. A. EDWARDS.

, DYNAMO ELECTRIC MACHINE. I N0.v,281,985. Patented July 24, 1883.

Y 50 Fig. 7 is an illustration in plan of the circum- UNITED STATES EDGAR A. EDWARDS, or CINCINNATI,

ASSIGrh OR TO OSCAR M. GOTTSGI-IALL,

TRUSTEE, OF DAYTON, OHIO.

DYNAMO-ELECTRIC MACHINE.

SPECIFICATION forming part of Letters Application filed May Patent No. 281,985, dated July 24, 1883. 68,1883. (Nomodehi To all whom, it may concern:

Be it known that I, EDGAR A. EDwARDs, a i citizen of the United States, and a resident of Cincinnati, in the county of Hamilton and State of Ohio, have invented certain new and useful Improvements in Dynamo-Electric Machines, of which the following is a specification.

One of the objects of my invention is to ill- Io crease the efficiency of the electro-generator by connecting the coils of the armature with the commutator in such a manner that each generating-coil of wire on the armature is brought into a shunt of low resistance before I 5 it arrives at the neutral or current-reversing points of the revolution, and the shunt cut out after the reversal, but maintaining a closed circuit at all times through all the coils.

Another object of my invention is to connect the collecting-brushes of the commutator to each other in circuit to the armature-coils in series, each brush and coil forming one of a series, and all being in a continuously-closed circuit, thereby maintaining a regular and constant supply of current to line by the revolu tions of the armature-coils. Themode of 0011- necting the inducting-coils of the armature with th e commutator, so as to maintain the continuously-closed circuit by shunt of low resistance for each coil while approaching, pass ing, and leaving the neutral or reversing point, is very important. It avoids sparks usually caused at the moment of current reversal; second, it prevents heating of the armature; third, 3 5 the shunting of each induction-coilbefore and during the reversal materially lessens the re sistance in the series of coils, thereby effecting a greatsaving of power employed in revolving the armature in generating electricity.

Figure 1 is a perspective view of my improvement, showing the armature removed from the field, with a diagram of the connections. Fig. 2 is a plan view of the commutator and brushes. Fig. 3 is a perspective view of the commutator with the insulating-disks removed. Fig. 4. is an end elevation of the commutator with the collecting brushes in working position. Figs. 5 and 6 are detail perspective views of parts of the commutator.

] ference or surface of the armature.

a central longitudinal section of the commutator and armature, showing a different mode of windingthe coils. Fig. 9 is a diagram illustrating the connections of the armature-coils with the brushes connected in circuit. Fig. 10 is a broken vertical cross-section of the field-helices and their cores and the polar cX- tensions.

A represents the base-plate of the dynamoelectric generator; B B O O, the field-magnets.

It represents the cores of these magnets.

D (Z represent segmental polar extensions of the cores.

E represents the armature, which is mounted upon a shaft and j ournaled concentrically with in the segmental extensions D (Z.

G represents a neutral yoke, which is rigidly connected to the cores of the coils B O, andthe cores of coils B O are rigidly connected to the iron base-plate A, which serves as a neutral yoke for the lower magnet. The coils are so wound and connected as that the segment D will be, say, of positive polarity, and the opposite polar extension, (1, is of negative polarity. These polar extensions D d have a space between their respective adjacent edges, which corresponds to the width of a coil wound on the armature, and these spaces form the neutral or current-reversing points of the ar mature.

6 represents the coils of the armature. They may be wound in any well-known manner.

Fig. 1 represents the Von Alteneck system of winding. Fig. 8 represents the De Romilly system of winding, but having the diametrically-opposite coils connected together, with their remaining ends connected to the opposite sections of the commutator-segments.

I I represent two series of collecting plates or brushes arranged so as to press on opposite sides of the commutator.

H represents the commutator. It is made in a series of sectional strips, t j, which are nearly semicircular, being insulated or separated from each other a slight distance.

K represents a series of metallic bridges, each having a hole pierced through the center, through which passes the armature-shaft.

Z represents segmental tenons, which occupy Fig. 8 is I V I I H gains or notches cut in one side of the hands if j, at their adjacent ends, as shown in Fig. 3. The ends of the tenons Z form a portion of the connnutator-periphcry, and also the contactpoint of the bridges with the brushes I I, and thus serve as circuit-connections during the period that the brushes are in contact with the tenons Z. These bridges must be made of low resistance compared with the coil, so that the electricity generated by thercmaining coils of the series is easily shunted through it while this coil is passing the reversing-point. This bridge K could be made of hard rubber or wood, facing the peripheral edges oi'the tenons with metal, and connecting the facings to each other by wire or other metallic connections.

71. represents insulating filling disk-pieces placed between the bridges K and the bands ij.

II represents a sleeve for rigidly connecting the commutator on shaft j. The commutator is shown as composed. of four series of strips, 77 arranged longitudinally on the armatureshai't, insulated or separated from. each other. The sect-ions or stripsvl j are also insulated from each other and from metallic contact with tenons I. There are as many longitudinal sections z'j of the commutator as there are induction-coils or series of induction coils wound on the armature. Thenumber of commutator-sections and armature-coils may be varied. Brushes I I are secured to the frame L by means of set-screws L, and insulated from metallic contact therewith. The series of tenons Z are arranged in spiral alternating series around the commutator, as shown in plan, Fig. 7, so that the tenons of the four series of bands 2' j are successively brought in contact alternately with. brushes I I. Just before each coil connected to eitherlongitudinal section arrives at the neutral point it is brought into shunt-circuit withitself and bridge K, while passing the currentreversing point, but maintains a continuoiisly-closed circuit {or all Y the coils. To connect the commutator in circuit with the coils I preferably employ transverse bolts 1 2 3 -11, which pass between sections 2' 7' and brid K and serve as binding-posts. Each band or strip j is mctallically connected (to one of these bolts) by means of cars 7 S, and each band j is mctallically connected to a similar bolt on the diainetrically-opposite side of the commutator.

The ends of. each of the coils c are respectively connected to opposite sets of bolts, one end of the wire being connected to, say, section 7?, and the other end to its opposing section. j, and the brushes are connected in series, so as to be shunted and reversed successively. It will be observed that the shunt sin-laces Z on the commutator are set into one side of the sections j, and the brushes press equally on the faces 6 and the sections of the strips/i j while that section of the commutator is in contact with the brush. The sections of i j, which abut the surfaces I, serve as connections for the divided branch of the circuit through the induction-coil connected to said sections 6 j, and the faces Z i'orm connections between a brush and (bridge for the other or) shunt-branch of the circuit during this period of time. This mode of connection is illustrated in diagram, Fig. 9, which shows their armature-coils c 0 c. The arrows indicate the direction of the current. Coil c is represented as in shunt or divided circuit by contact of brushes I I with the op 'iosing ends of bridge K. IVhen in this position, owing to the low resistance of the shunt K, the maxinnnn amount of current induced by the remaining coils is passing through this branch of the shunt, while a minimum amount will pass through the coil while in shunt. This mode of shunting each coil immediately be fore and until after it has passed the currentreversing point and passing the current of the remaining coils through the shunt 1naterially reduces the resistance on the working coils and increases the elliciency ol' the generator.

Numerals 10, 11, and 12 indicate the serial connections of brushes I I. The first serial brush, I, is connected to brush I of the next set, which is of opposite polarity, and so on through the series. They may, however, be connected in multiple-arc circuit.

M1 represent the connections of coils 13 C to the brushes, and L M represent the end of the coil B G to binding-posts O I, as shown in dotted line, Fig. l; coils B '3 being connected together, wound of one piece of wire, and coils O G are wound in like manner.

S T represent the metallic circuit, showing [our lamps connected in circuit.

In practice the commutators are set on the shaft so that each tenonlwill be a little in advance of the central radial. line of the coil of the series to which it is connected.

I claim 1. In combination with the armature of a dynamo-electric generator, a commutator com posed of duplex segments of rings upon diametrically-opposite sides of the shalt, insulated from each other at the two neutral lines, and having a segmental slnint-branch k I, forming a portion of the connnutatoesurlacc on each side of the two neutral points, so as to shunt the current in the coil connected thereto before, and continuing until after, passing the neutral line, and forming a transversebranch circuit through the connnutator without cutting the coil out of circuit, substantial] y as dcscribed.

o 2. In combinationwith an armature having a series of iinluction-coils, a series of duplex segmental commutators, i j, each provided with segmental shunt branch It Z, i'ormi n g a part of the comniutator-snriace on each side of the neutral lines and in juxtaposition with each end of both sections i j, the terminals of each coil being connected, respectively, with sections 5 and j in series, so that the terminals oi. each coil are broughtinto shunt-connection with the nals of each coil are brought into metallic connection with the branches is 1 before, and con tinuing until after, passing the neutral lines, and the current of remaining coils are shunted through the same branch 70 Z during said period thereby maintaining all of the coils at all times in continuous closed circuit, substantially as described.

In testimony whereof I have hereunto set my hand.

EDGAR A. EDWARDS.

\Vitnesses:

JNo. E. JONES, A. GLUOHOWSKY. 

